Fire-extinguisher.



Patented Apr. 1

W. G. SANDERSON. FIRE EXTINGUISHEH. APPLICATION FILED MAY I5. IsIe.

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UNITED STATES PATENT OFFICE.

WILLIAM G. SANDERSON, OF CHICAGO, ILLINOIS.

FIRE-EXTINGUISHER.

To all whom t may concern.'

Be it known that I, WILLIAM G. SANDER- soN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Fire-Extinguishers, of which the following is a specification.

My invention relates to improvements in fire extinguishers, and more particularly to one of the hand operated type, in which a suitable fire extinguishing fluid, such for example as ca-rbon tetrachlorid, is expelled from the container in a jet or spray by means of a hand impelled piston.

It is common practice in extinguishers of this; type to provide an axially fixed but rotatable screw extending through the center of the container and piston, the piston being threaded for eng-agement with the screw so that on the rotation of the latter the piston is 'forced inwardly to expel the fluid. One of the' faults inherent in such extinguishers is the difficulty of preventing leakageof the volatile Huid through the piston along the screw threads. impossible the threadson both the piston and screw must -necessarily be cut to permit free and easy relative movement, as a screw fitting sufficiently tight to stop theleakage would increase the frictional resistance to the operation of the extinguisher to a prohibitive degree. To secure the end of the screw to' the rear face of the piston would necessitate extending the screw stem thro-ugh the rear head of the container, obviously doubling the overall length of the apparatus. Aside from the clumsy appearance of such a/(structure'the long threaded rod would be exposed to injury such as bending, or mutilation of the threads, either of which `would render the extinguisher inoperative.

One of the objects of my invention is to provide an eliicient and reliable hand extinguisher in which an imperforate piston may be used, and to accomplish this I have provided what is termed atelescoping screw screw members inter-engage, one with the other, so that the overall-length ofthe screw when extended is ,approximately the col lapsed length multiplied by the ynumber lof Specification of Letters Patent.

As lubrication is wellA nigh y rejecting a-stream of fluid; screw members used. By using suchan arrangement'anyk suitable imperforate piston may be used, as it is secureddirectly to the screw, there being no relative movement 'of the two parts.

Patented Apr. 1,1919.` Application med May 15, 1916. serial No. 97,473. 1

Obviously the use ofsuch a'piston feeding c mechanism increases but little the overall length of the extinguisher casing and as the screw does not pass through the fluid containing chamber it may be suitably lubricated to facilitate its operation.

The principal object, therefore, ofl my invention is to provide a hand extinguisher in which a screw feed is used in combination with an imperforate piston, the overall length of the `extinguisher being but 'little greater than that of the type now in use.

Another object of my invention is to provide such an extinguisher in which an oval, or non-cylindrical casing is used to prevent rotation of the piston with respect to its imy peiling screw mechanism.

A further object of my invention is to provide an extinguisher 1n which the extinguishing fluid comes in contact only with' the walls of its container, thereby protecting the operating mechanism from chemical action.

Still other and further objects of my invention will become apparent to those skilled in the art from a consideration ofthe following description and drawings wherein- Figure 1 is a diametrical sectional view through my improved extinguisher.

Fig. 2 is a transverse sectional View on the line 2-2 of Fig. 1.

Fig. 3 is a fragmentary sectional view on the line 3-3 of Fig. V1, and 1 Fig. 4 is a diametrical sectional view through a modification.

The apparatus comprises in general a fluid chamber 10 within which is reciproca# bly mounted imperforate piston 11, which is forwardly impelled by means of the tele? scoping screw members indicated in general constructed of such asiz'e as to be-readily .10o by the operator. In operation theI userr in which a plurality of concentric tubular fcarried from place to place and discharged grasps the body ofthe chamber 10.*with one More SPeCally the'structure` `comprisesy va metal tube-'15 oflovalc'ross section pro'- vided with a concavcd head 16 which seained into its forward end, as at 17. A nozzle valve of any suitable type may be used, that illustrated comprising a nipple 18, internally threaded as at 19 to receive the threaded projection 20 of the winged nozzle 21. The nipple 18 is provided with an eccentric bore 22, whereas the bore 23 in the nozzle is concentric. Because of this arrangement' of non-alining bores it is obvious that when the winged nozzle is screwed to the innermost end of its travel, both bores are closed whereas a passage way is opened whenthe nozzle is rotated in the opposite direction.

A flanged head 24 closes the upper end of the tubular member 15 and is provided with a cylindrical extension casing 25 within which is mount-ed the telescoping feed screw. The feed screw comprises four partsa central threaded spindle 26 on the outer end of which is mounted the handle 13, and three concentric tubular screw members 27, 28 and 29. The upper end of the tubular member 27 is provided with an inwardly extendi ing annular shoulder 30 which is internally threaded for engagement with the threaded rod 26, its outer surface being screw threaded for engagement with a similar internally threaded shoulder 31, carried on nthe upper end of the tube 28. The outer surface of the tube 28 is similarly threaded for engagement with an internally threaded head 32, on the outer tube 29. A cap 33 is detachably secured on the lower end of the threaded rod 26 to prevent the threaded shoulder 30 from running over the end of the rod when it is turned down, and for the same reason I have provided outwardly projecting annula'r shoulders 34 and 35 on the lower ends of the tubes 27 and 28, respectively, for engagement with the shoulders 31, 32.

The piston which I have illustrated as comprising an oval late 36 carrying a packing disk 37 of suitable material on its inner face is secured to the inner or lower end 'of the tube 29. As asuitable means of securing the tube to the piston I have provided an outwardly formed annular bead or groove 38, perforated to receive a series of prongs 39 formed from the lower end of the tube 29, the ends of the prongs being turned over as at 40 to rivet the two parts together.

To prevent axial displacement of the cen- 'tizl threaded rod 26 I have provided an annular shoulder 41 near the upper end thereof for engagement by the cap nut 42 which is in screw threaded engagement with the upper end of the casing tube 25. A packing collar 43 overlies the upper' end of the tube 25 and engages the under side of the annular shoulder 41.

From the description it will be evident that rotation of the handle 13 causes the extension of the telescoping screw sections vpressing the pist-on 36 downward in thc cylinder and ejer-ting the iuid. As there are four extensible screw members provided in the embodiment illustrated in Fig. 1, it will be obvious'that the length of the casing 25 projecting from the head of the extinguisher need be but approximately a third the length of the extinguisher casing within which the piston travels. The screw may have either right or left hand threads depending uponl hand crank projecting from one side of.

the casing and carrying on its inner end a beveled pinion 51 engaging with a beveled gear 52, secured to the lower end of the outer tubular extensible screw member 53.`

In this instance the parts are reversed, that is, the outer tubular member is the rotated driving part whereas the inner screw threaded spindle 54 is connected at its lower end with the piston 36. In this embodiment I have shown but three extensible members, namely the inner threaded spindle 54, a concentric tube 53, having at its lower end an -internally threaded shoulder 56 .which engages with the threaded lspindle 54, and an outer axially fixed but rotatable shell meinber 53, the lower end of which is provided with a shoulder and internally threaded, as at 57, for engagement with the external threads on tube 55. The upper end of the shell 53 is provided with an outwardly extending annular flange 58 which is held from axial movement by the cap nut 59, screw threaded on the upper end of the inclosing casing turbe 60.

The operation of the mod ication illustrated in Fig. 4 is the same as that shown in Fig. 1 except that the screw movement is accomplished by a different driving mechanism.

Whereas I have illustrated and described but two embodiments of my invention it is obvious that various other modifications and changes may be made without departing v from the spirit and scope of the appended claims.

Having described my invention, what I claim is 1. In a hand operated lire extinguisher, the combination of a {iu-id containing tube, an imperforate iston reciprocable therein, a closure head or one end of the tube, a plurality of telescoping inter-engaging screw members, one of said members' being secured to the piston, a casing carried by the said head and inclosing the screw members when in telescoped position, and means projecting through said casing for rotating one of the screw members not connected with the piston.

2. In a hand operated vfire extinguisher, the combination of a fluid containing tube, an imperforate piston reciprocable therein, means for preventing rotation ofthe piston with respect to the tube, a threaded rod concentric With the tube and rotatable with respect thereto, means for preventing axial movement of the rod, a plunality of interengaging tubes telescoping one Within the other, the inner being in threaded engagement with the rod, and means for securing the outer of said tubes to the piston.

3. In a hand o erated fire lextingiusher the combination oi) a fluid containing tube, an imperforate piston reciprocable therein, means for preventing rotation of the piston with respect to the tube, a head for one end of the tube, an axiallyv disposed cylindrical casing, 'a plurality of internally and exter-v n-ally threaded tubes adapted to telescope within each other, the inner tube being in threaded en agement with the said rod and all of the tues, when in telescoped position lying within the casing, means connecting the outer of the tubes with the iston,-'and means carried by the outer end o? the casing for preventing axial movement of the threaded rod.

In testimony whereof I hereunto set my hand in the presence of two subscribing Witnesses.

WILLIAM Gr. SANDERSON. In the presence 01"- STANmaY W. COOK, MARY F. ALLEN. 

